* Stronger typing for the swarm handler future
* The swarm future is now a swarm stream of events
* Rewrite StreamMuxer in core
* Update libp2p_mplex for the new stream muxer
* Update yamux for new stream muxer
* Rewrite multiplex
* Increase the packet size limit to 32 MB
* Fix waiting for poll_complete to finish
* Typo
* Properly close substreams
* Add a limit to the number of substreams
* Add a limit to the length of the internal buffer
* Fix concerns